Lockable knee joint for orthopedic braces or artificial limbs



A ril 1, 1952 M. c. PETRUCH LOCKABLE KNEE JOINT FOR ORTHOPEDIC BRACES OR ARTIFICIAL LIMBS Filed Dec. 16, 1950 Mei/10421; 6/

A TTORNE).

Patented Apr. 1, 1952 LOCKABLE KNEE JOINT FOR ORTHOPEDIC BRACES OR ARTIFICIAL LIMBS Methodius Ciryllus Pctruch, Tampa, Fla.

Application December 16, 1950, Serial No. 201,166

.5 Claims.

This invention relates to improvements in lockable knee joint for orthopedic brace or artificial limb.

The principal objects of this invention are:

First, to provide a joint structure for an orthopedic brace which is easily locked or unlocked while in straight extended position of the joint.

Second, to provide a knee joint for orthopedic braces and artificial limbs which is highly resistant to wear under the loads applied thereto in walking.

Third, to provide lock structure for a knee joint of a brace which is covered or enclosed to prevent tearing or wearing of the clothing surrounding the joint.

Fourth, to provide lock mechanism for a knee joint which is extremely simple and easy to assemble and repair while at the'same time being through the upper brace member and lock engaging spring taken along the plane of the line 5-5 in Fig. 2.

Fig. 6 is a transverse cross sectional view through the brace joint and lock taken along the plane of the line 6--6 in Fig. 2.

Fig. 7 is a fragmentary side elevational view, partially in vertical cross section, of the brace joint and lock in bent position.

In the drawings I have illustrated one side of an orthopedic brace such as is normally worn on the knee of a partially disabled person. It should be understood that normally two of these 5 brace structures are employed, one on each side entirely positive and effective in its locking actirely by the main brace elements as distinguished from the pivotal connection therebetween.

Sixth, to provide a lockable knee joint for an orthopedic brace in which the principal stress encountered by walking on the brace is carried by the main elements of the brace and not transmitted to the lock elements whereby the lock structure is relatively small and long lived.

Other objects and advantages relating to details of my invention will be apparent from a consideration of the following description and claims. The drawings of which there is one sheet, illustrate a preferred form of my lock and joint as applied to the load carrying members of an orthopedic brace.

Fig. l is a fragmentary side elevational view of the joint and lock in the straight or extended position of the brace.

Fig. 2 is a fragmentary side elevational view of the joint with portions of the lock retaining sleeve broken away in vertical cross section along the plane of the line 2-2 in Fig. 6.

Fig. 3 is a transverse cross sectional view through the lock operating handle taken along the plane of the line 33 in Fig. 1.

Fig. 4 is a transverse cross sectional view through the upper brace member and lock operating finger taken along the plane of the line 4-4 in Fig. 2.

Fig. 5 is a transverse cross sectional view of the knee, and that suitable connecting and attaching straps or fixtures are provided for attaching the upper and lower sections of the brace to the leg of the wearer, both above and below the knee. As an alternative, the brace structure may be incorporated in an artificial limb in which case only the upper end. of the brace will be attached to the leg of the wearer and the lower brace will be built into an artificial lower limb.

The brace includes an upper brace member 1 of flat strap-like stock of the required rigidity and a lower brace member 2 of similar construction. The lower end of the upper brace member 2 is surrounded by and secured to a sleeve 3 of folded sheet metal construction. The lower end of the sleeve is provided with circular extensions 4 which project downwardly in lapped relationship on each side of the upper end of the lower brace member 2. A hinge pin or rivet 6 pivotally connects the circular extensions 4 with the lower brace member 2.

In order to relieve the hinge pin 6 from the main loads applied to the brace in walking, the upper end of the lower brace member 2 is provided with a segmental arcuate surface 1 concentric about the pin 6 and disposedtoward the front side of the brace. The lower end of the upper brace member 2 is provided with a mating segmental arcuate surface 8 so that when the brace is in straight extended position the weight of the wearer is directed through the upper brace member and the abutting surfaces 1 and 8 to the lower brace member 2.

In order to regulate and limit the pivoting motion of the upper brace member about the hinge pin 6 and lower brace member 2, the lower brace member is provided with a segmental arcuate surface 9 radially recessed inwardly from the bearing surface 1. The upper brace member is provided with a locking lug Ill which projects downwardly against the arcuate surface 9 and forms a limit stop coacting with the rear end of the bearing surface 1 to prevent forward overbending of the brace joint.

In order to prevent unintentional breaking or bending of the brace joint rearwardly, the

upper end of the lower brace 2 is provided on itsforward side with a locking notch II which extends as a chord of the arcuate bearing surface I. The lower endof" the upper brace member I has a forwardly opening notch as atl2 to align with the locking notch II when the brace is extended. A locking block 13 of rectangular cross section is slidable along the notch illinto locking engagement with the notch l I; ,The locking block I3 is approximately the same thickness as the brace membersl 'and'2 a'ndds slidably retained on the upper brace jmemb er' by the sides and forward edge wall 14 of the sleeve 3. A coil spring l5 retained in the'notch H by the sleeve 3 constantly urges the locking block idownwaifdly towarddockin'g engagement withthe lower brace inembe'rl It will thus be seen that when the; brace is extended to straight position, the locking block will snap into'engager'nent with the notch and prevent unintentional retraction or bending of the'brace. In" order to release the locking block 'a rfdpeiinit bending of the brace, the forward wall ,4 of the sleeve 3 i'ls'lc'ut away or slotted vertically iii can; The outer end of the pin 11" is sec'u 'edto a narrow lock operating finger is which ends vertically 'fupwardlyalongthe forward fsid "of the sleeve 3 and upper brace member I. T finger llf'is of reverselybentand tensioned 'inetal so" that t he upper end of the finger is constantly biased forwardlyofthe upper brace member ,l as mostclearly illustrated in Fig. 1. Adoop l9 onthe upper end of the'sleeve 3 reatilfi to passia pin I'I'securedto the lockin ta1ns the intermediate portion of the "finger I!) in alignment with lthe upper brace member I.

JfiI'he'upper end of the finger I 8 is secured within arearwardl'y'opening U-shaped clip 2!! as by being welded thereto and the rearwardly extendingflai iges 2| of the clip 20 are lapped over the sides 'ofitl e upper ibra'ee member II A pin 22 connecting the flangesof the clip 2| is" slidably disposed in a forwardly angled slot 23 in the pper br ce membe T in 22 carries s thly rounded knob or handpiece' 24 so that th ginger [8 can conveniently be reciprocated throughlthe clothing ofthe wearer.

P 1 ng engagement with thelowerbrace member yv en the brace is extended;

"From" the fore'g'oingitwill be apparentthat my brace structure can beselective'ly positioned andie'tained either locked, extended or unlockedpivoted position by a simple movement of theiknolo 24f lfartioular attention is directed t'clthe fact thatthe locking block i3 is not subjected to the heavy load carrying stresses of the brace aridds effectively guided in its locking and spring l5" to advance the locking block is into unlocking motion by the sleeve 3. In order that the locking block I3 shall be completely guided in its forward extended position, the lower end of the front wall Id of the sleeve is extended across the locking block below the slot I6 as at 26 and a notch for receiving this lower portion 26 is formed in the forward edge of the lower brace member as at 21.

Having thus described my invention, what I claim 'as =new and desire to secure by Letters Patentis:

1. A lockable leg brace structure comprisin elongated upper and lower brace members of strap-like structure, the adjacent ends of said members having mating concavo-convex arcuate bearing surfaces engaged in the aligned positions or said membersg'a radially recessed arcuate surface on the lower of said members adjacent the bearing surface thereon, a locking lug fixedly formed on the upper of said members and rotatable along said recessed surface into engagemenr'wuh tli'end'of the convex surface'in the 'ali'gnedpositionsof said'members, asleeve closely embracing and secured to the upper of 'said'r'neinbei s "and" having projecting side plates" lapped alongside the sides of the 10 g of said members. a hinge pin conne'cti'ng'said'side plates and said lower 'rnembenconcentrically with said bearin surface, a locking" not ch forrned'iri said lower member and intersecting the bearing surface thereon at the opposite end of thebearing from said recessed surface, said upper brace member being "longitudinally notched *underneath said sleeve'toprovidea slideway aligned with said lockingnotchdn the aligned" position of said members, a locking block slidable in said slideway "and"extens ible"into engagement with said lockin notch, a'spring in said slideway biasing said block to locking position, a block retracting finger of springable material secured at its lower end to said block and extending upwardly along the 2. A lockable leg brace structure comprising elongated upper and lower brace members of strap-like structure, the adjacent ends of said members having mating concavo-convex arcuate bearing surfaces engaged in the aligned positions of said members, a radially recessed arcuate surface on a first of said members adjacent the bearing surface thereon, a locking lu fixed on the second of'said members and rotatable along said recessed'surface into engagement withthe end of the reces's'for ning said recessed surface inthe aligned positions of said members, as fisi'e e b lfil embrac and'secured e of said members and having projectin side plates lapped alongside the end of the other of said members, a hinge pin connectingsaid side plates and said othermember concentrically with said bearingsurfaces, a locking notch formed in one of said members and extending in a chordal relation to the arc of said bearing surfaces, the other of said members being longitudinally notched to provide a slideway aligned with said locking notch in the aligned positions ofsaid members, a locking block slidable in said slideway and extensible into engagement with said lockin notch, a spring in said slideway biasing said block to locking position, a block retracting finger of springable material secured at its lower end to said block and extending upwardly along the front edge of the upper of said members, a clip on the upper end of said finger and lapped alongside of said upper member, a pin carried by said clip and projecting into said upper member, said upper member having a forwardly and downwardly angled slot receiving said pin, and a handpiece connected to said pin.

3. A lockable leg brace structure comprising elongated upper and lower brace members of strap-like structure, the adjacent ends of said members having mating concave-convex arcuate bearing surfaces engaged in the erected posi tions of said members, coacting stop surfaces on said members engageable in the erected 10051-1 tions thereof, a connecting piece secured to'the member having the concave bearing surface and having a projecting side plate lapped alongside the end of the member having the convex bearing, a hinge pin connecting said side plate and said last member concentrically with said hearing surfaces, locking notches formed in said members and aligned across said bearing surfacesin the erected positions of said members, a locking block slidable in one of said notches and extensible into engagement with the other of said locking notches, a block actuating finger secured at its lower end to said block and extending upwardly along the front edge of the upper of said members, and a pin carried by the upper end of said finger and projecting into said upper member, said upper member having a forwardly and downwardly angled slot receiving said pin.

4. Alockable leg brace structure comprising elongated upper and lower brace members, the adjacent ends of said members having mating concave-convex arcuate bearing surfaces engaged in the erected positions of said members, a stop surface on one of said members adjacent the bearing surface thereon, a locking face on the other of said members and rotatable into engagement with said stop surface in the erected positions of said members, a sleeve closely embracing and secured to said other of said members and having a projectin side plate lapped alongside the side of the said one of said members,

a hinge pin connecting said side plate and said one member concentrically with said bearing surfaces, a locking notch formed in said one member and extending along a line intersecting the arc of the bearing surface thereon and facing oppowith said locking notch in the erected position of said members, a locking block slidable in said slideway and extensible 'into engagement with said locking notch, a block retracting finger secured at one end to said block and extending along the upper of said members, and means on the upper end of said finger guidingly engaging the upper of said members.

5. A lockable leg brace structure comprising elongated upper and lower brace members, the adjacent ends of said members having mating concave-convex arcuate bearing surfaces ongaged in the erected positions of said members, a stop surface on a first of said members, a looking face on the second of said members and retatable into engagement with said stop surface in the erected positions of said members, means pivotally connecting said members concentrically with said bearing surfaces, a locking notch formed in said secondmember and extending in a chordal relation tothe are of said bearing surfaces and facing oppositely from the locking face on said second member, said first brace member being provided with a slideway aligned with said locking notch in the erected positions of said members, a locking block longitudinally slidable and transversely retained in said slideway and extensible into engagement with said locking notch, a block retracting finger of transversely springable material secured at its lower end to said block and extending upwardly along the upper of said members, said finger being transversely bent and tensioned whereby the upper end thereof is biased transversely of the upper of said members, a pin carried by the upper end of said finger andengaging said upper member, said upper member having an angled slot receiving said pin, and a handpiece connected to said pin.

METHODIUS CLHYLLUS PETR-UCH.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED sraTEs PATENTS .Number Name Date 540,764 Spring June 11, 1895 772,293 Reese Oct. 11, 1904 

